A Heartbeat and a Guitar tells of the collaboration of two distinct yet connected musicians—iconoclast Johnny Cash and pioneering folk artist Peter La Farge—and the album they created, Bitter Tears: Ballads of the American Indian. It also tells of the unique personal, political, and cultural struggles that informed this album, one that has influenced the likes of Bruce Springsteen and Bob Dylan.

D’Ambrosio has interviewed dozens of Cash’s and La Farge’s friends, family, and collaborators, including surviving members of his band, his producers, and Pete Seeger and Kris Kristofferson, creating a dramatic picture of both an era of radical protest and the making of one of the most controversial and enduring works of political pop art of the 1960s.